This section provides background information related to the present disclosure which is not necessarily prior art.
Manufacturers have introduced rotary power tools that have variable speed motors and multi-stage multi-speed transmissions. The tools may provide the user with sufficient control over the output speed and the torque of the tool so as to facilitate diverse operations without resorting to additional specialized tools. While the tools have performed satisfactorily, there remains room in the art for improvements to increase performance and reduce complexity and cost.
One manner for improvements to performance and the lowering of costs concerns the manner in which a transmission assembly can be mounted to the housing of a power tool. For example, U.S. Pat. No. 6,431,289 describes an arrangement in which the transmission assembly includes a transmission sleeve into which a reduction gearset assembly is received. The transmission sleeve includes first grooves that are configured to receive alignment ribs formed on mating handle shells to mount the transmission assembly to the handle shell in a manner that permits the transmission assembly to slide axially relative to the handle shell. Such configuration can be advantageous in some circumstances (e.g., the configuration permits the transmission assembly to be withdrawn from a handle shell assembly without separating the two handle shells from one another). We have determined, however, that improvements to the power tool are needed to facilitate more cost efficient volume production.